The lawn below the Royal Crescent Ha-ha, Bath A report on geophysical surveys by the Bath and Camerton Archaeological Society June and October 2012 Janet A. Pryke and John Oswin The lawn below the Royal Crescent Ha-ha, Bath The lawn is part of Royal Victoria Park in Bath, and this and is covered by MBN11272 “Royal Victoria Park” and DBN3598 which covers the nationally registered area (Grade II). It includes MBN30167 and MBN30168 Report on two geophysical surveys by the Bath and Camerton Archaeology Society ©2013 Janet Pryke and John Oswin 1 Summary The lawn below the Royal Crescent Ha-ha in Bath was part of an archaeological investigation in 2002 for a Time Team television programme on Channel 4. In this they confirmed the route of and excavated a known Roman road down across this lawn, and also excavated nearby burials. They also revealed and excavated a Late Bronze Age ditch. This project extends the geophysics part of this work, and demonstrated that the Late Bronze Age ditch is extended to an enclosure. This work also investigated a large ditch-like formation running from NE towards the SW across the lawn, and other features including an area with pit-like chambers below the ground. 2 Preface This survey was carried out by members of the Bath and Camerton Archaeological Society (BACAS), following the work done by Time Team in 2002 (“Death in a Crescent” on Channel 4), and also, as we subsequently found out, a survey carried out by Engineering Archaeological Services in 2006. The project arose from the interest of Janet Pryke in possible Roman military remains in the area. Additional geophysical description of the area was considered to be important and would also provide information for future archaeological work. BACAS agreed to support the project. John Oswin as BACAS Geophysics team leader coordinated the technical work. Many thanks are due to John Gater who has given us permission to use the Time Team geophysics results in this report. The geophysical investigation for Time Team was carried out by GSB Prospection, and from their work we knew that resistance analysis of the area gave significant results. The project was encouraged by Richard Sermon, B&NES Archaeological Officer, and helpful discussions have been had with him and Rod Millard, HER Officer. We are also grateful to the B&NES Parks Department for their support and permission to undertake this work. We have also had help and advice in several areas from many departments of the Council, including Graham Evans and Simon Memory (Parks), Mike Bransgrove (Property Services) and Phil Mansfield and Mark Williams (Building Control), and the former Head of the Parks Department, Stan Hitt. We acknowledge and appreciate the help, comments and advice that has also been given by Ian Brooks of Engineering Archaeological Services (EAS), Clare Baxter, Collections Manager of the Alnwick Castle collection, Stephen Clews and Susan Fox of the Roman Baths Museum, David Hughes of Bath Spa University and Maurice Tucker of Bath Geological Society, also the help from Colin Johnston and the Bath Record Office. Janet has appreciated the continuing encouragement of Amy Frost of Bath Preservation Trust. Through the project we have especially appreciated the support, guidance and advice from Marek Lewcun. Special thanks are due to the group of volunteers who were pleased to take an interest in and volunteer for the geophysics work, which was all performed very efficiently and positively. It included a very early start for the June work, and there was the threat of and actual very rainy weather over both periods, in what was a very wet year. The volunteers and helpers included Adam Aust, Rick Buettner, Sandra Heward, Chris Higgs, Denise Hillier, Dawn Hodgson, Mary Huntley, Andy Kingan, John Knapper, Tim Lunt, Patrick McCarron, Di Parkin, Ian Perkins, Sue Pickering, Emma Pryke, Susan Rhodes, and Richard Wyatt. 3 Table of contents Summary Preface Distribution List Table of Contents List of Figures 1 Introduction 1.1 Location 1.2 Background 1.3 Geology and vegetation 1.4 Scope 2 Method 2.1 Method 2.2 Constraints 3 Results 3.1 General 3.2 Details of magnetometry survey 3.3 Details of resistance survey 3.4 Resistivity profiling 3.5 Ground penetrating radar 4 Interpretation 4.1 The large ditch like feature across the lawn 4.2 The enclosure 4.3 The hole in the ground 4.4 Other observations 5 Comment 6 References Appendix A1 Data reconstruction and relocating the grid Appendix A2 Information on data archiving 4 List of figures Figure 1.1 Map of the area Figure 3.1 Magnetometry survey of lawn Figure 3.2 Resistance survey of eastern side of lawn Figure 3.3 Composite of resistance results from Time Team and this investigation Figure 3.4 a&b Resistance survey in south west area of lawn Figure 3.5 a&b Resistivity profiles near the corner of the enclosure Figure 3.6 a&b Resistivity profiles over linear anomaly running NW to SW over lawn Figure 3.7 Linked double resistivity profile over suggested site of void Figure 3.8 Ground penetrating radar over area including row of magnetometry signals Figure 3.9 Ground penetrating radar over void area 5 1 Introduction 1.1 Location The lawn surveyed is situated in front of the Royal Crescent in Bath and is part of the Royal Victoria Park. It is also known as Three Acre Piece. Its outline is marked in Figure 1.1. Figure 1.1 Map of the area All satellite maps ©Google Earth with grateful acknowledgements The Royal Crescent was built by John Wood the younger in 1767 on part of what were Upper and Middle Barton Fields as shown in a map of 17401. The land down from the Ha-ha then became known as the Crescent Fields. The survey area is between the Ha-ha in front of the Crescent and the path which continues the Gravel Walk. Over to the west, on the other side of the road that runs down by the lawn, Marlborough Buildings, is the area previously known as the Commons which now makes up the major part of the Royal Victoria Park. Down the hillside from the lawn towards the south east is Bath city centre, including the hot spring area, which is about 750m away. The Crescent and lawn are on an overall slope of about 1 in 20 down towards the River Avon, which is visible at the bottom left hand corner of Figure 1.1. This is beyond the Upper Bristol Road which is joined by Marlborough Buildings at a T junction. 6 1.2 Background The lawn area was added to the public areas of Royal Victoria Park in 18462. Its lower boundary was edged by a hedge, as described “to be restocked” in the drawing in John Wood’s 1764 lease documents3, above the path just north of the Barton Middle Field boundary 1. At some time there has been apparent another Ha-ha-like length of wall below the hedge and its path, and a photograph of this from about 1860 can be examined 4. There is no sign of this walling now and its position would be under the tree and shrub filled bank between the lawn and Royal Avenue. The lawn is part of a large area which, together with the Commons to the west, has been described over many years as “Never to be built on” as stated in the drawing in the John Wood lease documents3. The area of the lawn has been used for various purposes since the development of the Royal Crescent. It was the site of some of the works for the building works of the Crescent as pictured by Thomas Malton, where many types of stone workings are observed to be taking place in front of the almost-completed buildings5. As a field it continued to be used for grazing with the Ha-ha fulfilling its boundary role to keep the animals below the Royal Crescent. There are images of animals there through the years including up to the 1930s6. In 1850, there was a garden proposed for the whole area in front of the Royal Crescent7. This included pathways, walls, plantings and fountains. However this garden was not created and we presume that no preliminary work was done. Its area was described as park or ornamental ground in the one inch to the mile Ordnance Survey map published in 1893. In the Second World War the lawn area was taken over for use as allotments, and aerial photography shows the arrangement of the plots8, with their orientation at right angles to the path below the area. After the war these allotments continued to be cultivated until 1953, when they were removed. The hedge along the bottom of the area was removed at this time9. Following this, the area was lawned, and it is now very well used for leisure and picnicking, alongside its provision of an impressive site for special occasions. The wider area including this lawn had been important in more historical times, and contains many features of archaeological interest through the use and settlement of this part of the city. At earlier times there may have been standing stones visible from here. To the west, in that part of the Commons called Ring Common (after “The Ring” in Hyde Park according to John Wood the elder10), a group of four large stones was detected in excavations in 198511, buried under the level ground towards the top of the allotments behind Marlborough Buildings. Observations made at the time, included those of one pair described as “two large blocks of rough limestone set deep into the 7 clay and bearing marks on their surface to suggest that an original ‘standing’ portion of each was broken deliberately, some time in their past”.